Despite most forms of therapy, patients with oat cell carcinoma have a very short survival, and aggressive chemotherapy is warranted. Cyclophosphamide, adriamycin, and VP 16-213 have all been shown to be active agents for this disease. Thus, the combinations of three active agents appears to be warrented. Since response is of short duration in this disease a randomization to test the hypothesis of immunotherapy prolongation of the duration of remission is included. Eleven of fourteen patients entered into the program showed objective response (79%). There were four complete responses, four partial responses, one objective response less than a partial, and two patients with response that died. Two patients progressed on therapy. Hematologic toxicity was uniformly severe and resulted in the death of two patients from infection. MER toxicity included fever and local inflammation.